Lubricant composition



disadvantages.

United States Patent F LUBRICANT COMPOSITION Allan A. Manteulfel andWilliam D. Gilson, Crystal Lake, 111., assignors to The Pure OilCompany, Chicago, Ill., a corporation of Ohio No Drawing. Filed Aug. 28,1956, Ser. No. 606,585

6 Claims. (Cl. 252-333) This invention relates to lubricants and tolubricant additives, and more particularly to extreme pressurelubricants and to additives capable of imparting to mineral and otherlubricating oils high load-carrying ability, and to their method ofmanufacture.

The use of chlorine-, sulfur-, and phosphorus-containing compositions as13.1. lubricant additives is well nown. Each type of additive has itsadvantages and The halogen-containing additives, while capable ofimparting high load-carrying characteristics to oils, have thedisadvantage of being corrosive and hydrolyzing in service to formobjectionable acids. The ability of sulfur to impart high load-carryingcharacteristics to a lubricating oil is dependent on the activity of thesulfur, which in turn is dependent on the tightness with which it ischemically bound in a compound. Elemental or loosely bound sulfur, whileimparting high load-carrying characteristics, is too corrosive to beallowed to remain in an automotive differential or other gear assemblyover a long. period of time. The same is true of the phosphorussulfides. On the otherhand, sulfur and phosphorus sulfides when tightlybound chemically to organic compounds such as fatty acids, fatty esters,fatty alco hols and terpenes, impart excellent load-carryingcharacteristics to a lubricating oil and are substantially noncorrosive.However, additives of this type will not give the desired protectionagainst wear to new gears during the initial break-in period. 7

An object of this invention is to provide an extreme pressure lubricant.Another object of this invention is to provide a composition which canbe added to mineral and other lubricating oils to impart thereto extremepressure characteristics. A further object of the invention is toprovide a lubricant which will protect gears against Wear during theinitial break-in period and during the subsequent running life of thegears. Still another object of the invention is to provide a compositionwhich can be added to mineral oil and other types of lubricants toenable such lubricants to satisfactorily lubricate automotive gearsduring the initial break-in period and during the subsequent runninglife thereof. A still further object of the invention is to provide anextreme pressure lubricant which will satisfactorily lubricate gearassemblies during the initial break-in period and during the subselquent running life thereof Without causing undue corrosion of the gearelements. Still another object is to provide a method for making theaforesaid compositions and lubricants.

Other objects of the invention will become manifest from the followingdetailed description of the invention.

We have discovered that by incorporating in alubrieating oi! sulfurizedand phosphorized fatty material and free sulfur, sulfides of phosphorusand/or unstable organic polysulfides which liberate sulfur under serviceconditions, the lubricant will afford satisfactory protection andlubrication for the gear assembly during the initial break-in period andduring the subsequent running life of the gears without producingharmful corrosion 2,968,619 Patented Jan. 17, 1961 thereof. During theinitial break-in period the sulfur, in conjunction withthesulfurized-phosphorized fatty material, affords anti-weld protectionto the gears. As the gear-tooth contact areas for load-carrying becomeestablished and as a lesser degree of anti-weld protection is required,the active sulfur or sulfur compound gradually reacts with thesulfurized-phosphorized fatty material to form a non-corrosivecomposition, and the resulting oil continues to impart to the oilextreme-pressure properties without causing undue corrosion.

As sulfurized and phosphorized compositions which are effective for thepurpose of our invention we prefer sulfurized and phosphori zed fattybodies such as those made in accordance with Whittier et al. Patent2,211,306. As therein disclosed, such sulfurized and phosphorized fattybodies are prepared by sulfurizing a fatty material such as vegetable,animal, or marine oils and waxes, including but not limited to woolgrease, cotton seed, castor, rape seed, sperm and lard oils, andsynthetic esters of high molecular weight, mono-unsaturated fatty acids(C C24), such as glyceryl trioleate, propylene glycol dioleate andbutylene glycol dioleate, at a temperature of approximately 330-340" F.with elemental sulfur until a satisfactory copper strip test isobtained, and then phosphorizing the sulfurized material with aphosphorus sulfide, preferably phosphorus sesquisulfide, at atemperature of about 220230 F. until a satisfactory copper strip isobtained.

Instead of following the process setforth in the aforesaid Whi-ttier etal. patent, the initial sulfurization step may be terminated prior tothe time a satisfactory copper strip test is obtained, that is, when thecopper strip shows a tan color, and then phosphorized with a phosphorussulfide for a sufficiently long period of time to more firmly bind thesulfur and phosphorus. This method is particularly effective wherehigher amounts of phosphorus sesquisulfide within the limits of thosedisclosed in the aforesaid patent are used in the phosphorization step.As a specific example, lard oil was mixed with 7.5% of sulfur and thenwas stirred with constantagit-ation in a kettle at a temperature of325-340 F. Heating was continued for approximately four hours, at whichtime the copper strip gave a tan color upon immersion in a sample of theproduct at 300 F. for one minute. The mixture was then rapidly cooled toapproximately 220 F., 0.8% by weight of phosphorus sesquisulfide wasslowly added in finely divided form, and the reaction was allowed tocontinue at 220-230 F. for a period of eight hours, after which themixture was rapidly cooled to F. and thereafter allowed to cool to roomtemperature. The final product contained 7.85% sulfur and 0.45%phosphorus by weight, and gave a tan color in the copper strip test at220 F. for one minute.

In preparing sulfurized-phosphorized fatty materials in accordance withthe method just described, the fatty material may be reacted with about5 to 10% of sulfur in the first stage and with from about 0.4 to 5% ofphosphorus sesquisulfide or equivalent amount of other phosphorussulfide in the second stage. This method of preparingsulfurized-phosphorized fatty materials, in which sulfur is not tightlybound in the first stage and relatively largeamounts of phosphorussulfide are reacted in the second stage, is disclosed and claimed in'the co -pending application of P. R. Chapman and A. Manteuffel, SerialNO. 553,419.

The sulfurized-phosphorized lard oil bases used'in the blends reportedin the ensuing Table I were made as follows: I 4

Base (1) was made by heating 91.7 parts by weight of lard oil to 285,plus or minus 10 F., and then dusting in slowly with agitation 7.5 partsby weight of splfur. After the addition of the sulfur the temperaturewas vor more sulfur atoms in the molecule.

an ammonium or amine salt of sulfonic acids. "acids suitable forpreparing the salts are the mahogany raised to 335, plus or minus F.,and held at that level for four hours. At the completion of the heatingperiod a copper strip was immersed in the bath for three minutes and wasonly slightly tarnished.

The temperature of the reaction mixture was then lowered to 220 F.,.plusor minus 5 F., and 0.8 part by weight of phosphorus sesquisulfide wasslowly added. This temperature level was maintained for eight hours withcontinuous mechanical agitation of the reaction mixture. At the end ofthis period a copper strip immersed in the bath at 220 F. for threeminutes gave a pink coating, indicating that the reaction was completed.

The sulfurized-phosphorized lard oil (2) of Table I was made by heating92.5 parts of lard oil to 285, plus or minus F., and slowly dusting in 5parts by weight of sulfur with continuous mechanical agitation. The

temperature of the batch was then raised to 335, plus or minus 5 F., andheld for three hours. After this period of heating, a copper stripimmersed in the bath for three minutes was lightly tarnished.

The temperature of the bath was then lowered to 220, plus or minus 5 F.,and 2.5 parts by weight of phosphorus sesquisulfide was slowly dustedin. The batch was held at this temperature level for twelve hours withcontinuous stirring, that is, until a copper strip immersed in the bathfor three minutes had a pink coating.

Sulfurized and phosphorized lard oil base (3) was made in the samemanner as base (2) except 5% of phosphorus sesquisulfide was addedinstead of 2.5% and heating at 220, plus or minus 5 F., was continuedfor 18 hours, at which time a copper strip immersed in the bath forthree minutes had a pinkish coating.

Instead of using elemental sulfur in conjunction with thesulfurized-phosphorized fatty material, we may add to the oil anunstable sulfur compound which will release elemental sulfur as, forexample, dibenzyl trisulfide or other alkyl, aryl or arylalkylpolysulfides containing three A phosphorus sulfide such as phosphorussesquisulfide suspended or dissolved in the mineral oil will alsofunction to provide the anti-weld properties for which the elementalsulfur is added. If desired, both sulful and a phosphorus sulfide suchas phosphorus sesquisulfide may be used in combination within the limitsof the amounts specified above for sulfur. If a sulfur-liberatingcompound is used, it should be added in amounts sufficient to liberatethe desired amount of sulfur.

In preparing lubricants in accordance with our invention, we have foundthat it is advantageous to add to the lubricant a substance which willpromote the reaction of the sulfur with the sulfurized and phosphorizedfatty oil or ester so as to shorten the break-in period or the periodduring which corrosive sulfur is present in the suitable for thispurpose, we prefer lead naphthenate because of the additionalload-carrying characteristics which it imparts to the oil during thebreak-in period.

We have further found that reduction of sulfur activity andcorrosiveness of the gear oil can be still further accelerated byadding, as a fourth constituent of the oil, Sulfonic sulfouation ofmineral lubricating oil stocks with sulfur trioxide, as well as sulfonicacids resulting from the sulfonation of pure hydrocarbons, such assubstituted and unsubstituted naphthalene. A compound which has beenfound to be effective for this purpose is the ethylene diamine salt ofdinonyl naphthalene sulfonic acid. Other sulfonates which are suitableare the ammonium salts of oil-soluble sulfonic acids obtained from thesulfonation of solvent-refined neutral oils with sulfur trioxide.

In preparing gear oils in accordance with our invention, the sulfur oractive sulfur-containing compound is dissolved in a portion or all ofthe mineral oil at a temperature of about 270-290 F. After the additionof the sulfur or active sulfur compound is complete, the temperature ofthe oil is reduced to about 200 F. before adding thesulfurized-phosphorized fatty material. It is important to reduce thetemperature to this level to avoid immediate or rapid reaction of thesulfur with the sulfurized-phosphorized fatty body. A suitabletemperature of admixture of the sulfur-containing oil and thesulfurized-phosphorized fatty body is about -200 F.

The manner of mixing the several constituents together or the order inwhich they are admixed is not important, provided temperatures areproperly adjusted to a level which will permit solution of the additivesin the oil within a reasonable period of time without causingsubstantial reaction between the active sulfur and thesulfurized-phosphorized fatty material. The sulfurizedphosphorized fattymaterial, dibenzyl disulfide, naphthenate salt, and sulfonate salt, aswell as other additives such as pour point depressors, V.I. improvers,and antifoam agents, may be added separately to the oil or may beadmixed together and added as an admixture. They may be dissolveddirectly in the oil in which the sulfur or active-sulfur compound hasbeen previously dissolved, or they may be admixed with a portion of theoil to which the sulfur or active-sulfur compound has not been added andthis portion added to the portion containing the sulfur or active-sulfurcompound. We prefer to add dibenzyl disulfide, or equivalent disulfideas disclosed in claims in Reissue Patent 22,911, in order to improve theload-carrying properties of the oil. We also, preferably, incorporate inthe finished lubricant a sufficient amount of aromatic extract obtainedin the solvent extraction of mineral lubricating oil fractions by meansof phenol, furfural, nitrobenzene and equivalent solvents to preventprecipitation.

In order to realize the benefits of our invention, it is necessary toadjust the proportions of sulfurizedphosphorized fatty material andsulfur, or active-sulfur compound, so that the active sulfur is absorbedor inactivated by the sulfurized-phosphorized material and does notremain in the oil in a corrosive form over a long period of time. If theratio of sulfur or activesulfur compound to sulfurized-phosphorizedfatty material is too high, the sulfur will not be completely absorbedand the, corrosive condition of the gear oil will continue for anindefinite period of time with resultant harmful wear of the gear parts.Not only will the amount of sulfur which can be chemically absorbed bedetermined by the amount of the sulfurized-phosphorized fatty oil andother materials present, but also by the amount of sulfur bound in thesulfurized-phosphorized material. A sulfurized-phosphorized materialcontaining a relatively low amount of bound sulfur as, for example, 5%by weight, enables the use of a larger amount of free sulfur or activesulfur-containing material than does a sulfurized-phosphorized materialcontaining a higher amount as, for example, 10% of bound sulfur. Ingeneral, we have found that an amount of sulfur or equivalent activesulfur-containing compound between 1 and 50% of the quantity ofsulfurized-phosphorized fatty material is effective in providing initialanti-weld characteristics to the oil during the break-in period and ofbeing subsequently absorbed or reacted with the sulfurized-phosphorizedfatty material to a substantially nn-c0rrosive state. We prefer anamount of sulfur equivalent to about 3 to 10% by weight of thesulfurizedphosphorized fatty material.

The amount of free sulfur or active sulfur-containing compatibility ofthe additives, particularly sulfurizedphosphorized lard oil, in thefinished oil and to inhibit precipitation.

After the sulfur had been dissolved in a portion of material to be addedwill be determined to some extent the mineral oil the remainder of theoil was added, by the nature of the gears to be lubricated. Forexresulting in cooling of the solution to below 200 F. ample, in thecase of phosphate-coated gears the number Sulfurized-phosphorized. lardoil, dibenzyl disulfide, lead of miles required for breaking them in isprobably not naphthenate and the ethylene diarm'ne salt of dinonylsulmore than 100 and may be as low as 25 to 50. In such fonic acid werethen added as indicated in the specific cases, therefore, it may bedesirable to incorporate blends. During the addition of these additives,the oil smaller amounts of sulfur so that the sulfur will be was atatemperature between 160 and 200 F. The tembound in an inactive ornon-corrosive form within a perature was maintained below 200 F. toavoid preshort period of time, probably not more than 24 hours. matureinactivation of the sulfur. On the other hand green gears, that is,gears which After all the constituents had been added to the oil, arenot precoated, are usually considered to be broken the completed blendswere placed in an oil bath at in after 500 miles of recommended drivingspeed. In 200 F. and subjected to a three minute copper strip suchcases, sufficient sulfur should be present so that it test upon reachingbath temperature, i.e., in about a will not be completely bound beforethe end of the half-hour, Thereafter, the oil was maintainedcontinuperiod required to drive 500 miles, which on an average ously ata temperature of 200 F. and subjected to the may be approximately oneweek. copper strip test after one hour, two hours, twenty-four Theamount of sulfur required in the oil to furnish hours, and one week. Thetemperature of 200 F. was anti-weld protection during the necessaryperiod of breakselected as representing the average temperature to whichin can be approximated by subjecting an oil blend to the gear oils aresubjected in service. The sulfurized and copper strip test, performed byimmersing aclea n copper phosphorized lard oil used in the blends givenin the strip for three minutes in the oil maintained at a temensuingtable was made in the manner previously deperature of 210 F. Theappearance of the strip after scribed in this application and covered inapplication this test provides an indication of the amount of cor-Serial No. 553,419, now U.S. Patent No. 2,910,438. In rosion whichoccurred and hence the extent to which the each case the period forsulfurization was four hours active sulfur has been bound in anon-active form. If v and the period for reacting the phosphorussesquisulfide the color is light peacock or tan, the sulfur issubstanwas eight hours. tially non-corrosive. As the color of the stripprogresses From an examination of the table, the following conthroughmedium peacock, light brown, medium brown, clusions can be reached: (1)by comparison of blends 1 mottled brown, brown-black and black, itindicates that and 2 it is seen that the gear oil was less corrosiveafter the oil is more and more corrosive.- one hours heating at 200 F.when it contained S,P In order to demonstrate the effectiveness ofcompolard oil in addition to sulfur than when it containedo-nly sitionsmade in accordance with our invention, a number sulfur alone; (2) bycomparison of blends 2, 3 and 4 of blends were prepared and subjected tothe copper it can be deduced that sulfurized and phosphorized lard stripcorrosion test. The blends tested and thecorrosion oil containing alesser amount of sulfur and a greater tests on each blend are given inthe following table. 4 amount of phosphorus sesquisulfide chemicallyabsorbs Blends were made by dissolving free sufur in approxithe activesulfur more rapidly than S--P lard oil containmately half of the totalmineral oil, previously blended, ing a greater amount of sulfur and alesser amount of at a temperature of 270-290 F. with stirring. The totalphosphorus sesquisulfide; (3) by comparison of blends 1 mineral oilconsisted of a blend of neutral oil, bright and 6 it can be deduced thatdibenzyl disulfide has no stock and solvent extract. These threeconstituents were significant effect in reducing the corrosivity of thegear blended together to give the desired finished viscosity oil; (4) bycomparison of blends 5 and 7 it is apparent and V1. The extract oil wasused to insure complete that the lead naphthenate accelerated theabsorption of Table I Blend No. Composition in parts by weight of gearoil Nesigtrfall oil, 200 SUS, viscosity at 100 F. 46.7-.-" 46.7".--46.7---" 40.7.-. 46.7-.-" 46.7"--. 46.7. Brggg siz oizk, 160-170 SUS,viscosity at 212 22.0.--" 22.0 22.0 22.0 22.0..-" 22.0..... 22.0. Phenolextract Suliur 0.3 S-P lard oil 9.0 Dibenzyl di fi 0.8 .l Leadnaphthenate (30% Pb) Ethylenediamine dinonyl naphthalene vsulloriiate.

ittite F R19 934 1 945 s97 771 983 9 1 887. at 130 330.23-..- 386.1,.-.387.65-..- 390.2 3725-..- 31121..-. 4062.- 346.6 3901.... 370. at21074.4"-.- 83.5-.-" s5.5 s4.3 82.4..." 72.9-- s5.1 .19..." 83.8..... 82.0.Viscosity Index 81 92 96. 9' 93. 82 l 93.0 3 Min. Cu strip test, uponreaching bath loose mottled flaky gray mottled brown brown black. mediumbrown temp. (200 F.). black black black black brown. black black brownblack 3 Min. Cu strip test, after 1 hr. at 200 F--- do.. .do do. dodo-do do loose medium Do.

black. pea}; C00 3 Min. Cu strip test, after 2hr. at 200 F.-. do -.do.do.. do do do... mggirlmn do.-. do Do. 3 Min. Cu strip test after 24 hrat 200 F do do mottled mottled do do do do do Do.

brown. brown. 3Min. Cu strip test,aiter lweek at 200 F.. do.. -do domedium do do light do. tan Do.

brown. brown.

1 Suliurized and phosphortzcd lard oil made by reacting 91.7% lard oil,7.5% S and 0.8% P48 2 Sulturized and phosphorized lard oil made by reactng 92.5% lard 911, 5.0% S and 2.5% P 8 5 Suliurized and phosphorizedlard oil made by reacting 90% lard 011, 5.0% S and 5.0% ns the activesulfur into a non-corrosive state; (5) by comparison of blends 7 and 8it is evident that in the absence of the SP lard oil the leadnaphthenate was ineffective to accelerate the absorption of the activesulfur; (6) comparison of blends 7 and 9 indicates that the ethylenediamine salt of dinonyl sulfonic acid further accelerated the absorptionof the active sulfur so that at the end of one week the product obtainedwas substantially noncorrosive.

Although the blends were all prepared using sulfurizedphosphorized lardoil with or without lead naphthenate and .the ethylene diamine salt ofdinonyl sulfonic acid,

other fatty oils or esters of high molecular weight fatty acids may beused in place of lard oil in making the sulfurized-phosphorizedadditive, as previously set forth. Likewise, other naphthenates andamine salts of sulfonic acids can be used in place of the specific saltused in the specific blends.

The amount of sulfurized and phosphorized fatty material in the blendmay range from about 5 to 20% by weight and the amount of dibenzyldisulfide which may be used in the blends may vary within the limitsdisclosed in Reissue Patent 22,911, but preferably between 0.5 and 2%The amount of naphthenate salt effective to accelerate the reaction ofsulfur with the sulfurizedphosphorized lard oil may vary betweenapproximately 0.1 and 5% by weight of the gear oil blend. The amount ofammonium or amine salt of sulfonic acid required to accelerate thereaction will be dependent on the particular compound chosen, the amountof active sulfur present, and the desired rate of sulfur inactivation.In general, amounts between 0.1 and 5% of the total gear oil blend areeffective.

The amount of solvent extract in the blend may vary from to 100% of themineral oil portion,,depending upon the desired V.I. and thecompatibility characteristics of the finished 'blend. In general,amounts from to 30% will prevent precipitation and at the same time givean oil with a commercially desirable V.I. The solvent extract used inthe blends reported in the foregoing table had the followingcharacteristics:

Any solvent extract of high aromaticity (above 50%), obtained byextraction of mineral lubricating oil fractions with solvents selectivefor separating parafiinic from aromatic hydrocarbons, may be used inplace of the specific extract used in preparing the blends given in theforegoing table.

We claim as our invention:

1. A lubricant composition characterized by initiall high antiweldproperties and decreasing corrosivity with extended use at elevatedtemperatures, consisting essentially of a petroleum lubricating oil,sufficient amount of a sulfurized-phosphorized fatty material, in therange from about 5-20 percent wt. of the composition to enhance theload-carrying properties of the oil, said sulfurized-phosph-orized fattymaterial being prepared by heating at least one ester of a non-dryinghigh-molecularweight fatty acid with 5-10 percent wt. of sulfur at325-340 F. until a tan copper strip end-point is obtained after oneminute immersion of a copper strip at 300 F., then heating thesulfurized ester with 0.4-5 percent wt. of phosphorus sesquisulfide at220-230 F. until a tan copper strip end-point is obtained after oneminute immersion of a copper strip at 220 R, an amount of elementalsulfur in the range from about l-50 percent wt. of thesulfurized-phosphorized fatty material sufficient to enhance theantiweld properties of the composition but not in excess of that amountwhich can react with the sulfurized-phosphorized fatty material to theextent necessary to convert the sulfur to a substantially non-corrosiveform upon extended use, and an amount of a naphthenate salt, in therange from about 0.1-5

' percent wt. of the composition, sufficient to accelerate the APIgravity 13.2 COC flash, F. 550 C00 fire, F. 640 SUS viscosity:

at 100 F. 34,000

at 150 F. 2,824

at 210 F. 404 Viscosity Index 17 Pour pt., F. +65 Carbon res.(Conradson)4.23 Sulfur, total, percent w 2.39 Neut. No. (ASTM D974) 2.8

reaction of the sulfur with the sulfurized-phosphorized fatty material.

2. A lubricant composition in accordance with claim 1 in which thenaphthenate salt is lead naphthenate.

3. A lubricant composition in accordance with claim 1 which contains asubstance from the group consisting of ammonium and amine salts ofsulfonic acids in an amount, in the range from about 0.1-5 percent wt.of the composition, sufficient to accelerate the reaction of sulfur andsulfurized-phosphorized fatty material.

4. A lubricant composition in accordance with claim 1 in which thepetroleum lubricating oil contains 9 percent wt. ofsulfurized-phosphorized lard oil, 0.8 'percent wt. of dibenzyldisulfide, 0.3 percent wt. of sulfur, about 4 percent wt. of leadnaphthenate, and sufiicient aromatic extract obtained in the solventextraction of mineral lubricating oil fractions to prevent precipitateof the aforesaid constituents from the lubricant composition.

5. A lubricant composition in accordance with claim 3 in which thesulfonic acid salt is the ethylene diamine salt of dinonyl naphthalenesulfonic acid.

6. A lubricant composition in accordance with claim 4 containing about 1percent wt. of the ethylene diamine salt of dinonyl naphthalene sulfonicacid.

References Cited in the file of this patent UNITED STATES PATENTS2,212,899 Flaxman Aug. 27, 1940 2,322,209 Prutton June 22, 19432,382,115 Stucker Aug. '14, 1945 2,480,873 Musselman Sept. 6, 19492,580,005 Cyphers Dec. 25, 1951 OTHER REFERENCES ASTM Standards onPetroleum Products and Lubricants, pub. by ASTM, Phila., Pa. November1956 pages -94.

Georgi, Motor Oils and Engine Lubrication, Reinhold Pub. Corp., 1950,pages 20, 180 and 181.

1. A LUBRICANT COMPOSITION CHARACTERIZED BY INITIALLY HIGH ANTIWELDPROPERTIES AND DECREASING CORROSIVITY WITH EXTENDED USE OF ELEVATEDTEMPERATURES, CONSISTING ESSENTIALLY OF A PETROLEUM LUBRICATING OIL,SUFFICIENT AMOUNT OF A SULFURIZED-PHOSPHORIZED FATTY MATERIAL, IN THERANGE FROM ABOUT 5-20 PERCENT WT. OF THE COMPOSITION TO ENHANCE THELOAD-CARRYING PROPERTIES OF THE OIL, AND SULFURIZED-PHOSPHORIZED FATTYMATERIAL BEING PREPARED BY HEATING AT LEAST ONE ESTER OF A NON-DRYINGHIGH-MOLECULARWEIGHT FATTY ACID WITH 5-10 PERCENT WT. OF SULFUR AT325*-340*F. UNTIL A TAN COPPER STRIP END-POINT IS OBTAINED AFTER ONEMINUTE IMMERSION OF A COPPER STRIP AT 300*F., THEN HEATING THESULFURIZED ESTER WITH 0.4-5 PERCENT WT. OF PHOSPHORUS SESQUISULFIDE AT200*-230*F. UNTIL A TAN COPPER STRIP END-POINT IS OBTAINED AFTER ONEMINUTE IMMERSION OF A COPPER STRIP AT 220*F., AN AMOUNT OF ELEMENTALSULFUR IN THE RANGE FROM ABOUT 1-50 PERCENT WT. OF THESULFURIZED-PHOSPHORIZED FATTY MATERIAL SUFFICIENT TO ENHANCE THEANTIWELD PROPERTIES OF THE COMPOSITION BUT NOT IN EXCESS OF THAT AMOUNTWHICH CAN REACT WITH THE SULFURIZED-PHOSPHORIZED FATTY MATERIAL TO THEEXTENT NECESSARY TO CONVERT THE SULFUR TO A SUBSTANTIALLY NON-CORROSIVEFORM UPON EXTENDED USE, AND AN AMOUNT OF NAPHTHENATE SALT, IN THE RANGEFROM ABOUT 0.1-5 PERCENT WT. OF THE COMPOSITION, SUFFICIENT TOACCELERATE THE REACTION OF THE SULFUR WITH THE SULFURIZED-PHOSPHORIZEDFATTY MATERIAL.